1. Field of the Invention
The invention relates in general to a noise estimation apparatus and a method thereof, and more particularly to a noise estimation apparatus for calculating a noise in an image frame and a method thereof.
2. Description of the Related Art
As multimedia applications progress at a fast pace in the recent years, requirements on image quality are also continuously raised. Multimedia images are often interfered by noises, which degrade the image quality by not only reducing clearness and sharpness but also blurring object outlines of the image. To eliminate image noises, a noise estimation technique is generally implemented in an image processing system to serve as a basis for noise reduction.
However, during the process of noise estimation, details or dynamic image contents in the image are frequently misjudged as noises in the image. Thus, the image processed by noise reduction may quite the contrary given a degraded image quality if noise reduction is performed based on the above misjudgment.
Therefore, there is a need for a noise estimation technique that effectively determines a noise level of image contents to prevent details or dynamic image contents from being misjudged as noises.